Background: Tumor necrosis factor-alpha (TNFɑ) is a cytokine that manages the host defense mechanism, which may play a role in the pathogenesis of COVID-19 patients. Several single-nucleotide polymorphisms, described in the promoter region of the TNFα gene, have a significant role on its transcriptional activity. These include the − 308A > G polymorphism which increases the TNFα levels with the expression of the A allele. The aim of this study was to explore whether the TNFα.− 308A > G polymorphism affects the clinical state of COVID-19 patients. The study included a total of 1028 individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which were distributed in 3 groups: asymptomatic, mild symptomatic and severe symptomatic patients. The amplification-refractory mutation system was used to determine the genotype of the TNFα.− 308A > G polymorphism.Results: Results show a higher tendency of being asymptomatic in individuals carrying the GG genotype (336 of 411; OR 1.24, 95% CI 0.91–1.70). The development of a severe form of SARS-CoV-2 infection was not found in subjects with the A allele compared to those with the G allele (OR 0.96, 95% CI 0.51–1.79), except in the eastern region of the country where the risk increased (OR 4.41, 95% CI 1.14–17.05). However, the subjects carrying the A allele had a higher chance of developing symptoms (OR 1.24, 95% CI 0.91–1.70) compared to those with the G allele.Conclusion: The TNFα.− 308A allele has an influence on developing symptoms of COVID-19 in Cuban patients, and that it particularly increases the risk of presenting severe forms of the disease in the eastern region of the country.

Objectives: A growing set of drugs includes a pharmacogenetic biomarker as a requirement before prescription. This study aims to determine the frequency of allelic variants with functional repercussions in clinically relevant pharmacogenes and its relation with genomic ancestry in Cuban individuals. Methods: 10 single nucleotide variants (SNVs) across eight genes, included in the list of genetic variants required for the prescription of warfarin, tacrolimus, azathioprine, simvastatin, carbamazepine, abacavir and clopidogrel were analyzed. From genotyping in 948 Cuban individuals, population frequencies and Hardy–Weinberg equilibrium assessment were determined using PLINK v1.9. As a result of the ADMIXTURE analysis, previously performed on this sample, the relationship with the individual proportion of contribution of European, African, Native American and Asian ancestry was evaluated. Results: Minor allele frequencies (MAFs) ranged from 0.0216 to 0.2781. Hardy–Weinberg equilibrium (HWE) deviations in three variants ( CYP2C9 rs1799853, HLA-A rs1061235 , SLCO1B1 rs4149056) were identified. Among individuals presenting the SNVs CYP2C9 rs1799853, CYP4F2 rs2108622, SLCO1B1 rs4149056, HLA-B rs2395029, the average European ancestry was higher; in contrast, individuals with the variant CYP3A5 rs10264272 presented higher African ancestry. Conclusions: The variability in the analysis of each included allele, is representative of the genetic heterogeneity of the Cuban population and provides a remarkable example of diversity among populations.